如何使用字典替换Pandas系列中的多个子串？

Question

我有一个熊猫系列的字符串.我想对每行的多个子串进行多次替换,请参阅:

testdf = pd.Series([
    'Mary went to school today',
    'John went to hospital today'
])
to_sub = {
    'Mary': 'Alice',
    'school': 'hospital',
    'today': 'yesterday',
    'tal': 'zzz',
}
testdf = testdf.replace(to_sub, regex=True)  # does not work (only replaces one instance per row)
print(testdf)

在上面的例子中,所需的输出是:

Alice went to hospital yesterday.
John went to hospizzz yesterday.

注意第一行有三个字典替换.

除了逐行(在for循环中)之外,我怎样才能有效地执行此操作？

我df.replace(...)在其他问题中尝试了许多其他答案,但只替换了一个子字符串,结果如下:Alice went to school today,在哪里school和today没有被替换..

另外要注意的是,替代应该发生一次全部用于任何单行.(参见hospital第一行中是未被取代的一第二时间hospizzz这将是错误的).

Answer 1

您可以使用：

#Borrowed from an external website
def multipleReplace(text, wordDict):
    for key in wordDict:
        text = text.replace(key, wordDict[key])
    return text

print(testdf.apply(lambda x: multipleReplace(x,to_sub)))

0    Alice went to hospital yesterday
1     John went to hospital yesterday

编辑

使用字典如下所述：

to_sub = {
'Mary': 'Alice',
'school': 'hospital',
'today': 'yesterday',
'tal': 'zzz'
}

testdf.apply(lambda x: ' '.join([to_sub.get(i, i) for i in x.split()]))

输出：

0    Alice went to hospital yesterday
1     John went to hospital yesterday